Copter-3.3 beta testing

Warning #1: an issue has been found with Tower's Pause button which can cause the vehicle to fly to an old position if the vehicle has not sent a position update to Tower in some time.

Warning #2: Copter-3.3.2 fixes a bug found in Copter-3.3.1's desired climb rate initialisation which could lead to a sudden momentary drop when switching from Stabilize or Acro to AltHold, Loiter or PosHold.

Warning #3: Copter-3.3.2 fixes an issue found in Copter-3.3.1 which could lead to hard landings in RTL or AUTO if the WPNAV_SPEED_DN was set too high (i.e. >400 or 4m/s) and/or the WPNAV_ACCEL_Z was set too low (i.e. <100 or 1m/s/s).

Warning #4: a bug was found in Copter-3.3 which could cause a sudden crash if you abort a Take-off initiated from a ground station.  Video description is here.  The bug is fixed in Copter-3.3.1 so we recommend upgrading.

Note #1: AC3.3-rc8 corrected a long standing bug in the HDOP reporting.  HDOP values will appear about 40% lower than previously but this does not actually mean the GPS position is better than before.
Note #2: if upgrading from AC3.2.1 the vehicle's accelerometer calibration needs to be done again.
Note #3: set SERIAL2_PROTOCOL to "3" and reboot the board to enable FrSky telemetry like in previous versions.
Note #4: the wiki will be updated over the next few weeks to explain how to use the new features

Copter-3.3.1 is available through the mission planner.  The full list of changes vs AC3.2.1 can be see in the ReleaseNotes and below are the most recent changes since AC3.3.

Sadly this version (and all future versions) will not run on the APM2.x boards due to CPU speed, flash and RAM restrictions.

Changes from 3.3:

1) Bug fix to prevent potential crash if Follow-Me is used after an aborted takeoff

2) compiler upgraded to 4.9.3 (runs slightly faster than 4.7.2 which was used previously)

Changes from 3.3-rc11:

1) EKF recovers from pre-arm "Compass variance" failure if compasses are consistent

Changes from 3.3-rc10:

1) PreArm "Need 3D Fix" message replaced with detailed reason from EKF

Changes from 3.3-rc9
1) EKF improvements:
    a) simpler optical flow takeoff check
2) Bug Fixes/Minor enhancements:
    a) fix INS3_USE parameter eeprom location
    b) fix SToRM32 serial protocol driver to work with recent versions
    c) increase motor pwm->thrust conversion (aka MOT_THST_EXPO) to 0.65 (was 0.50)
    d) Firmware version sent to GCS in AUTOPILOT_VERSION message
3) Safety:
    a) pre-arm check of compass variance if arming in Loiter, PosHold, Guided
    b) always check GPS before arming in Loiter (previously could be disabled if ARMING_CHECK=0)
    c) sanity check locations received from GCS for follow-me, do-set-home, do-set-ROI
    d) fix optical flow failsafe (was not always triggering LAND when optical flow failed)
    e) failsafe RTL vs LAND decision based on hardcoded 5m from home check (previously used WPNAV_RADIUS parameter)

Thanks for your testing!

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  • Hi, I wonder how long it can take autotune process? a 450 cuad after 18 minutes and he had no battery and the second attempt 15 minutes and never finished. :(
    Sorry for my English
    attach the log


    • Developer

      Hi Jose,

      I can't download your logs but 15 minutes isn't unusual depending on your tune and how many times you had to reposition. Yaw especially can take some time but that has been improved in rc6.

      As people have already told you, you can tune single axis at a time.

    • I had the same problem on a 450.  Solved it by doing autotune on pitch and roll, only, on one battery and yaw on another battery.  You can do this by setting Autotune_Axes parameter according to the following values: 

      7 All
      1 Roll Only
      2 Pitch Only
      4 Yaw Only
      3 Roll and Pitch
      5 Roll and Yaw
      6 Pitch and Yaw

      Good luck

    • You can autotune axis by axis, check (search for AUTOTUNE_BITMASK ).

      My 470 sized quad took about 12minutes for a full run, total time depends on the frame and conditions.

      • My tarot 650 took 12 mins too (for the whole lot)...

        • my new tarot 690 build took 14min for first autotune and 11 min for second.

          in 3.2 longest autotune time was 7 min, may be.  

          • Yes I can confirm that, mine 690S tooks also +/- 7min to complete the AutoTune with v3.2


            Like Erkki already have say you can use AUTOTUNE_BITMASK and do each axis separatly.

  • Randy or leonardt, I just had an interesting flight on 3.3rc5 it is a fairly short flight which ended up in crash w/o much damage.

    basically after a take off, my tried and true (running rc5 for several weeks now) copter started acting strangely and at the end of the 3rd minute it started dropping left arm RCout2 rather smoothly it was not an abrupt stop like a mechanical failure but I think lasted several seconds to me.  

    After going through the logs I am failing to understand why AC commanded minimum to RCout2 while the copter was continuing to roll left? 

    Thank you!

    2015-06-24 20-08-31 8.bin

    • Developer

      Hi Artem,

      I must be missing something because I can't see what you are talking about here.

      Could you put up a screen shot showing us what you are referring to?

      • Sorry, I guess, a bit much stress and I was looking on the wrong log, totally my mistake. In the correct log AC does what it should, but ESC/motor doesn't react as they should. My bad, this looks like a hardware failure. Looking in the log it does look as everything happened rather fast :), but to my perception the fall lasted several seconds, while IRL it happened in less than in a second..... I guess stress, the copter had at that time gimbal and a camera. My bad, again. If anyone interested here is the log (should be a correct one this time)

        2015-06-24 19-36-11.bin

This reply was deleted.


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